Merge pull request #18 from Nimac0/Collision

Sliding along collision boxes

include/ColliderComponent.h

@@ -3,6 +3,7 @@
 #include <SDL.h>
 
 #include "Component.h"
+#include "Vector2D.h"
 
 class TransformComponent;
 
@@ -15,10 +16,14 @@ public:
 	bool hasCollision; //added for removing collision of destroyed projectiles
 	float hitboxScale; //adds a seperate variable for the scale of the hitbox (not the sprite) so each sprite can have a different hitbox size if needed
 
+	bool isProjectile = false;
+
 	ColliderComponent(const char* tag);
 	ColliderComponent(const char* tag, float hitboxScale);
 
 	void init() override;
 	void update() override;
     void removeCollision();
+
+	void handleCollision(Vector2D& characterPos, SDL_Rect& characterCollider, SDL_Rect& componentCollider);
 };

include/Game.h

@@ -4,6 +4,8 @@
 #include <SDL_image.h>
 #include <vector>
 
+#include "Vector2D.h"
+
 class AssetManager;
 class ColliderComponent;
 

src/ColliderComponent.cpp

@@ -25,6 +25,10 @@ void ColliderComponent::init()
 		entity->addComponent<TransformComponent>();
 	}
 
+	if (strcmp(this->tag, "projectile") == 0) {
+		this->isProjectile = true;
+	}
+
 	transform = &entity->getComponent<TransformComponent>();
 	Game::colliders.push_back(this);
 }
@@ -43,3 +47,16 @@ void ColliderComponent::removeCollision()
 {
 	this->hasCollision = false;
 }
+
+void ColliderComponent::handleCollision(Vector2D& entityPos, SDL_Rect& entityCollider, SDL_Rect& componentCollider)
+{
+	// collision to right of character
+	if (entityPos.x < componentCollider.x)
+	{
+		entityPos.x = componentCollider.x - entityCollider.w;
+	}
+	else // collision to left of character
+	{
+		entityPos.x = componentCollider.x + componentCollider.w;
+	}
+}

src/Game.cpp

@@ -260,11 +260,25 @@ void Game::update()
 	{
 		if (SDL_HasIntersection(&player.getComponent<ColliderComponent>().collider, &cc->collider) && strcmp(cc->tag, "player") && cc->hasCollision)
 		{
-			player.getComponent<TransformComponent>().position = playerPos;
+			if (!cc->isProjectile)
+			{
+				player.getComponent<ColliderComponent>().handleCollision(player.getComponent<TransformComponent>().position, player.getComponent<ColliderComponent>().collider, cc->collider);
+			}
+			else
+			{
+				player.getComponent<TransformComponent>().position = playerPos;
+			}
 		}
 		if (SDL_HasIntersection(&enemy.getComponent<ColliderComponent>().collider, &cc->collider) && strcmp(cc->tag, "enemy") && cc->hasCollision)
 		{
-			enemy.getComponent<TransformComponent>().position = enemyPos;
+			if (!cc->isProjectile)
+			{
+				enemy.getComponent<ColliderComponent>().handleCollision(enemy.getComponent<TransformComponent>().position, enemy.getComponent<ColliderComponent>().collider, cc->collider);
+			}
+			else
+			{
+				enemy.getComponent<TransformComponent>().position = enemyPos;
+			}
 		}
 	}
 

src/TransformComponent.cpp

@@ -44,12 +44,29 @@ void TransformComponent::update()
 	// if(velocity.x != 0 && velocity.y != 0)
 
 	float multiplier = velocity.x != 0 && velocity.y != 0 ? 0.707 : 1; //normalizes vector
+
 	Vector2D newPos(
 		position.x + velocity.x * speed * multiplier,
 		position.y + velocity.y * speed * multiplier
 	);
-	if (newPos.x < 0 || newPos.x + (this->width * this->scale) > SCREEN_SIZE_WIDTH || newPos.y < 0 || newPos.y + (this->height * this->scale) > SCREEN_SIZE_HEIGHT)
-		return;
+
+	if (newPos.x < 0)
+	{
+		newPos.x = 0;
+	}
+	else if (newPos.x + (this->width * this->scale) > SCREEN_SIZE_WIDTH)
+	{
+		newPos.x = SCREEN_SIZE_WIDTH - (this->width * this->scale);
+	}
+
+	if (newPos.y < 0)
+	{
+		newPos.y = 0;
+	}
+	else if (newPos.y + (this->height * this->scale) > SCREEN_SIZE_HEIGHT)
+	{
+		newPos.y = SCREEN_SIZE_HEIGHT - (this->height * this->scale);
+	}
 
 	position = newPos;
 }